• Title/Summary/Keyword: Gardner

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A Study on the Timing Recovery using Peak Detector in Underwater Acoustic Communication (수중음향통신에서 Peak Detector를 갖는 시간동기회복에 관한 연구)

  • Han, Min-Su;Kim, Ki-Man
    • Journal of Navigation and Port Research
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    • v.36 no.5
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    • pp.371-378
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    • 2012
  • This paper presents a timing recovery method using Gardner TED (Timing Error Detector) with a Peak Detector using Parabola Peak Interpolation in underwater acoustic communication. This method will have an eye to improve phase converge speed of timing recovery and reduced amount of Tx data. The OQPSK(Offset Quadrature Phase Shift Keying) modulation technique was considered. The proposed algorithm has faster recovery speed and more accurate than Gardner TED because the sampling values in the proposed algorithm are moved persistingly to maximum or minimum point using parabolic peak interpolation. when simulation performed using Preposed method, it improved BER (Bit Error Rate) performance about 23% And to evaluate the performances of the proposed algorithm the sea trial was performed in the Korean East Sea. And distance of a transmitter-receiver is 3 km each other. As a result, the proposed algorithm outperforms better BER performance about 20% of timing recovery than the Gardner method. Also Proposed method improved converge speed of timing recovery about 1.4 times better than Gardner method.

Gardner Syndrome Showing Multiple Osteomas in the Jaws

  • Kim, Yongsoo;Lee, Sun Jae;Baek, Jin-A;Ko, Seung-O;Leem, Dae-Ho
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.35 no.6
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    • pp.421-426
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    • 2013
  • Gardner syndrome, an autosomal dominant inherited condition, is a subtype of familial adenomatous polyposis. It causes lesions in bones, skin, and teeth, as well as multiple gastrointestinal polyps, which, if left untreated, become malignant. Because patients with colorectal cancer have a low survival rate, early diagnosis and treatment of Gardner syndrome is critical. Therefore, the characteristic lesions of Gardner disease that appear on the face, jaws, and oral cavity must be understood; these can be evaluated by oral and maxillofacial clinicians. This report describes a case that was diagnosed and treated earlier with the help of a routine oral and maxillofacial examination and has had a seemingly good prognosis so far.

Extracolonic manifestations of Gardner syndrome: A case report

  • McKenzie C. Blackwell;Bhushan Thakkar;Andres Flores;Wenjian Zhang
    • Imaging Science in Dentistry
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    • v.53 no.2
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    • pp.169-174
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    • 2023
  • Gardner syndrome has head and neck manifestations that may be recognized during dental visits. Features such as multiple gnathic osteomas, impacted supernumerary teeth, and multiple foci of idiopathic osteosclerosis can be easily identified on dental radiographs, prompting the clinician to refer the patient for further investigation. A dental examination and routine radiographs play a vital role in revealing the extracolonic presentation of Gardner syndrome, which facilitates timely screening and detection of colorectal cancer and other malignancies associated with this condition. This report discusses the case of a 50-year-old Caucasian man who presented with a hard swelling of the left angle of the mandible and was diagnosed with Gardner syndrome based on abnormal findings from an oral examination, dental imaging, and medical and family history.

Gardner syndrome associated with multiple osteomas, intestinal polyposis, and epidermoid cysts

  • Koh, Kwang-Joon;Park, Ha-Na;Kim, Kyoung-A
    • Imaging Science in Dentistry
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    • v.46 no.4
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    • pp.267-272
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    • 2016
  • Gardner syndrome is known as a variant of familial adenomatous polyposis. This syndrome is characterized by multiple intestinal polyposes, osteomas, and epidermoid cysts. In addition, dental abnormalities include an increased frequency of multiple odontomas, as well as supernumerary and impacted teeth. The authors report the case of a 7-year-old male patient with Gardner syndrome. Radiographic findings revealed multiple osteomas in both sides of the maxilla, multiple diffuse enostoses in both jaws, and a complex odontoma in the left mandibular body. Two years later, multiple epidermoid cysts on the scalp were found. Since this patient was suspected to have Gardner syndrome, the authors recommended gastrointestinal endoscopy to check for intestinal polyposis. Gastrointestinal endoscopic examination revealed multiple polyposes in the upper gastrointestinal tract and fundus of the stomach. As a result, the final diagnosis was Gardner syndrome.

Timing recovery based on zero-crossing detection for multi-level PAM signals (영점교차검출에 의한 다중레벨 PAM 신호의 타이밍 복원)

  • 김정권;이용환
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.22 no.10
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    • pp.2246-2255
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    • 1997
  • Gardner proposed an algorithm for timing recovery of BPSK/QPSK signals based on zero-crossing detection technique. When Gardner's method is applied to multi-level PAM signals, it suffers from increased timing jitter due to self noise. To alleviate this problem, an improved algoritjm is proposed in this paper. The timing function is modified so that it zero point at the transition of PAM signals, that results in remarkable reduced timing jitter. The performance of the proposed algorithm is analyzed and compared to that of Garner's one. Finally, analytical results are verified by computer simulation.

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Traumatic Pseudoaneurysm of the Superficial Temporal Artery due to Gardner Traction

  • Lee, Hyun-Seok;Jo, Kwang-Wook;Lee, Sun-Ho;Eoh, Whan
    • Journal of Korean Neurosurgical Society
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    • v.48 no.3
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    • pp.291-293
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    • 2010
  • We report a case of pseudoaneurysm of the parietal division of the superficial temporal artery (STA) secondary to iatrogenic head injury due to Gardner traction. A 54-year-old man presented with a pulsatile, cystic, and painless mass in the right anterior temporal region which developed three weeks after head fixation via Gardner traction. At the time of discovery, the mass was 10 mm in diameter, compressible and disappeared after manual compression of the proximal STA. A bruit was audible over the mass, which was thought to be a pseudoaneurysm. A computed tomography angiogram (CTA) showed a pseudoaneurysm of the parietal division of the right ST A. The tip of the pseudoaneurysm was thrombosed and was both red and tender. The pseudoaneurysm was thought to be filled with infected thrombus, and the mass was resected with ligation of the proximal and distal ends of the STA. A pseudoaneurysm of the STA should be suspected when there is a history of possible vessel injury, such as a history of head-pin fixation, and when a patient presents with a pulsatile, cystic mass near the temple. Pseudoaneurysms can be successfully treated by excision.

Timing Recovery Algorithm with Slop Compensated for Multi-level PAM Signals (Multi-level PAM신호에 적용 가능한 기울기 보상 심볼타이밍 알고리즘)

  • 전광호;임명섭
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.26 no.11A
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    • pp.1864-1871
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    • 2001
  • In this paper, new symbol timing recovery algorithm is proposed, which is suitable for the digital communication system with Multi-level PAM signals. In the newly proposed symbol timing recovery algorithm, the timing error function is derived by compensating the several difference values between sampled symbol and neighboring symbol every symbol period with mid samples and decided symbol values. Conventional symbol timing recovery methods did not work well in Multi-level PAM signals, but the newly proposed method can be applied to Multi-level PAM signals as well as QPSK. For the performance analysis, the derived variance of the timing error function and the timing error characteristics of S-curve show that the proposed method has better performance than Gardner method and the modified Gardner method.

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A New Carrier Phase-Independent Discrete STR Algorithm for Sampled Receiver (샘플수신기를 위한 반송파위상에 독립적인 이산 STR 알고리듬)

  • 김의묵;조병록;최형진
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.18 no.4
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    • pp.561-571
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    • 1993
  • In this paper, a new discrete Symbol Timing Recovery (STR) algorithm, is proposed. This algorithm is derived from the optimum estimation theory. The algorithm combines the advantages of Mueller and $M\"{u}ller$ algorithm and Gardner algorithm, and avoids some of their shortcomings. The implementation of the new timing detector is simple and the combined operations of Carrier Recovery (CR) -STR is possible because the operation of the new STR is independent of the carrier phase. On the other hand, the behavior of nonlinear characteristics in the new algorithm is analyzed and explained. The performance evaluation is accomplished in detail by numerical calculations and Monte-Carlo simulations. In these respects, this algorithm is similar to Gardner's algorithm, but in tracking performance due to pattern jitter at small rolloff, the proposed algorithm is superior to Gardner's algorithm.

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Performance evaluation of symbol timing recovery for direct broadcating via satellite (DBS용 심볼동기앍리즘의 성능평가)

  • 김용훈;이경하;최형진
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.33A no.10
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    • pp.1-11
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    • 1996
  • In this paper, we evaluate the performance of DD-bardner (decision-directed gardner) algorithm. We derive an analytic gain of the thiming detector that is a function of SNR and an excess bandwidth, and verify the result by simulation. We also compare the DD-gardner algorithm with the bardner algorithm with respect to tracking performance and jitter performance under low SNR and a residual frequency component.

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Stable Isotope Measurement of Ammonium Using HPLC-RTS (high performance liquid chromatography-retention time shift) (HPLC-RTS (high performance liquid chromatography-retention time shift)를 이용한 암모늄 이온의 안정동위원소 측정방법의 개선)

  • An, Soonmo;Lee, Jiyoung;Gardner, Wayne S.
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.18 no.1
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    • pp.47-52
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    • 2013
  • Despite the usefulness of nitrogen isotope tracer experiments in nitrogen cycling studies, there are not such many measurement data mainly due to the difficulties in analytical methods. Although Gardner et al. (1996) developed a relatively simple and accurate method that can measure ammonium isotope using HPLC and used it widely in various N dynamics studies, the technique was not adopted to other laboratories. An HPLC-RTS system using updated HPLC pumps that can perform the same measurements as that of Gardner et al. (1996) was built. The result of standard sample showed linear increase of RTS with the $^{15}N$ proportions. Centroid retention times calculated with Matlab$^{(R)}$ program enhanced the linearity of the response. In a sea water incubation experiment spiked with $^{15}NH_4{^+}$, the uptake and regeneration of ammonium could be separately estimated using the temporal change of $^{15}N/^{14}N$.